Reappraisal of the Regnauld Procedure for Hallux Valgus and

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$closure of deep fascia in ankle fracture surgery - The Podiatry Institute$

CHAPTER 18 8I 1. Piot Hole - 2mr Drill lnitially D.ill wdh 0.062" K-wi.e Enlarge wiih 2.0 mm Dril Bat 2. Dillwith Stop - 2.4 mm D.il Enlarge ONLY Phalangeal Base 3. Depth Measuaemeni Generally 28-30 mm lengih 4. Tap enti.e Lenglh ih.ough Latera, C€dex of Phalengeal Head 5. lnserl Herbeft Screw so comp elely lnaraosseus 6. Remove P.elimr.ary Fxalion (0.045" KVt4 7. lnsed 2nd Foinl ofFixation 0.062" KW anse*ed from Distal Tip otToe Cross both IPJ of Hallux & Osteotomy the wire through the articular surface; remember that the phalangeal articular surface is concave. This wire, the "rudder pin" will remain until the base is reinserted later in the procedure (Figure 4). It provides a reference point so that articular congruency will be maintained as well as providing a point for handling the fragment. If the surgeon chooses, alternatively the base may be left in place with dissection limited to that necessary for osteotomy and fixation. For full decompression, the basal fragment is then extirpated from the wound with care so as to minimize damage to its structure. The bone may be soft and this often means avoidance of the points of bone forceps to grasp the base during excision. A 6 inch Brown forceps or guarded pressure with an alligator bone forceps is usefui. Following its removal from the wound, the resected portion of proximal phalanx is wrapped in a damp sponge for later use. The surgeon may now address the proliferative bone or arthrosis of the first meratarsal. If the operadve pathology is one of hallux valgus, only limited dissecrion of the first metatarsal is necessary. In cases of severe deformity or first MTP joint arthrosis then additional dissection may be required. This allows adequate exposure for peripheral cheilectomy of the osteophytosis. A sesamoidolysis may be performed with inspection of all surfaces of the metatarsal head and its sesamoids. Cheilectomy or removal of peripheral lipping of the sesamoids is possible as well as complete removal of a sesamoid if deemed necessary is quite easy from an intracapsular approach with the base removed from the wound. Alternativeiy, the base need not be excised but complete subperiosteal dissection along the medial aspect of the base of the proximal phalanx is necessary for both later internal fixation as well as providing some degree of joint rela-xation. With the phalangeal base removed from the wound, tethering of the flexor tendons to each other may be accomplished to aid in hallucal purchase and help avoid later interphalangeal joint instabiliry postoperatively (Figure 5). A hallux maileus was identified in some of the early cases postoperatively and this is now a routine maneuver to avoid this complication. The excised portion of the phalangeal base is remodeled. A]l soft tissue attachmenrs ro the base should be removed. Usually, this is begun with a rongeur followed by decortication of the periphery of the base performed with a rotary drill and side-cutting oval or round bur (5 mm). The hand rongeur is also helpful in resecting the periarticular lipping or osteophytosis that may be present. Following remodeling, a small kirschner wire is used to perforate the entire remaining corrical surface a few millimeters to aid in revascularization and avoidance of avascular necrosis (Figure 6). These holes are similar to those placed in any bone graft to encourage revascularization. A 0.028 inch kirschner wire is utilized to drill 25 to 35 holes around the entire osseous circumference of the phalangeal base. Here, care must be taken to avoid drilling into the articular surface due to the concave geometry of the articular surface. The wound is copiously irrigated and the graft is reinserted using the "rudder pin" as a reference or guide to its placement to re-establish a congruous first MTP joint. A0.045 in. kirschner wire placed from the medial surface ofthe re-inserted base into the lateral cortex ofthe phalanx is used for preliminary fixation. Definitive fixation is performed with insertion of a Herbert or Bold screw. Fixation with the Herbert bone screw will be described as this has been the most common form of fixation performed, Figure 7. Fixation with a Herbert bone screw inserted from the plantar medial aspecr of the base into the distal lateral aspect ofthe phalanx has been very effective. Alternatively, the Bold Screw has been used
82 CHAPTE,R i8 as the screws are similar but the latter is cannulated with a simplified insertion technique. Other fixation alternatives have been utilized over the years but generally the Herbert (Zimmer, \7arsaw, IN) or Bold (\Tright Medical Gchnology Group, Arlington TN) screws have yielded rigid fixation with no extra-osseous prominence. PILOT HOLE An AO type triple drill guide is useful as a guide to drill the 2.0 mm pilot or core diameter hole. The drill guide has a pointed edge that allows placement of the drill hole on the edge of the osseous/articular surface along the plantar medial aspect ofthe base of the proximal phalanx. The hole is drilled from plantar medial to dorsal lateral and distal direction. Actually, the preferred technique is to form the initial screw hole with a 0.062" kirschner wire as this is stiff and can be maneuvered more easily then a drill bit. Subsequently, this is enlarged it with a 2.0 mm drili by hand. DRILL WITH STOPX The 2.0 mm hole in the base is enlarged with the 2.4 mm Herbert drill with stop; this a hand instrument that allows for this overdrill only a short segment of the phalangeal base. This accommodates the larger diameter of the trailing thread of the Herbert bone screw. DEPTH MEASUREMENT A small fragment depth gauge can then be used to measure the correct length screw necessary. Alternatively, a 0.045in kirschner wire is inserted by hand and then clamped with a hemostat. The length of wire inserted is then compared to a ruler. This has shown to be a reliable and accurate technique. The exact length screw to that measured may be inserted, generally a 28 or 30 mm screw. Note no countersinking is performed. TAP+ The entire depth of the pilot hole is tapped with the 3.0 mm Herbert tap equivalent to the thread of the leading 3.0 mm thread of the Herbert screw. It is important to cut the thread through the entire portion of phalanx to avoid later difficulties wirh screw inserrion. SCREW' INSERTIONX The appropriate length screw is inserted using some axial pressure as the screw advances until it lies completely within the substance of bone. A 28 or 30 mm screw is most commonly used so that the leading thread may just perforate the opposite cortex for solid purchase of bone. FINAL PREPARAIION AND SECONDARY STABILIZAIION The kirschner wire used as preliminary fixation as well as the "rudder pin" may then be removed and any overhang between the base and the shaft can then be remodeled. A second point of fixation has been found useful both for increasing the rigidity of the screw fixation as well as for stabilization of the hallucal interphalangeal joint. A 0.062 in kirschner wire is driven from the tip of the toe in a proximal manner crossing the IP joint as well as the osteotomy. Irrigation is again performed followed by capsular and skin closure per surgeon's preference. Immediate weight bearing in a surgical shoe is allowed and the procedure may be performed bilaterally on an out-patient basis. Immediate range of motion is encouraged as this is a joint salvage procedure in a patient usually with evidence of joint disease or preoperative limitation of .ioint movement. POSTOPERAITVE CARE Generally, a Darco (Darco International, Huntington, \(rV) or Reese type surgical shoe is utilized postoperatively for 3-4 weeks. Thereafter, a gym shoe or soft leather shoe is allowed. Immediate range of motion is possible due to the stability imparted by the internal fixation. tWhen the base is completely excised, my preference is to continue to splint the hallux for a period of time usually with a bunion splint for 6 weeks. Very predictable bone healing can be expected with the technique described with almost complete absence of avascular necrosis. Complete bony union within 3 months is the rule. This procedure also does not address metatarsus primus elevatus or a long first metatarsal as observed in many cases of hallux rigidus. Careful preoperative assessment is mandatory for successful results. Our experience with this procedure has been very grati$/ing
Page 1 and 2: CHAPTER I8 RE,APPRAISAL OF THE, RE.
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Reappraisal of the Regnauld Procedure for Hallux Valgus and

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